No evidence that nitrogen enrichment affect fungal communities of Vaccinium roots in two contrasting boreal forest types

• Published in: Soil biology & biochemistry 2010-02, Vol.42 (2), p.234-243
• Main Authors: Ishida, Takahide A., Nordin, Annika
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biochemistry and biology; Biological and medical sciences; Boreal forest; boreal forests; Chemical, physicochemical, biochemical and biological properties; Community structure; Economic plant physiology; Ericoid mycorrhizal fungi; fertilizer rates; Forest Science; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; genetic markers; Herpotrichiellaceae; molecular sequence data; nitrogen; Nitrogen addition; nitrogen fertilizers; Nitrogen, phosphorus, potassium fertilizations; nucleotide sequences; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Picea abies; Pinus sylvestris; population density; restriction fragment length polymorphism; root systems; Skogsvetenskap; soil fungi; Soil science; Soil-plant relationships. Soil fertility. Fertilization. Amendments; species differences; species diversity; Symbiosis (nodules, symbiotic nitrogen fixation, mycorrhiza...); temporal variation; Terminal restriction fragment length polymorphisms (T-RFLP); understory; Vaccinium myrtillus; Vaccinium vitis-idaea
• ISSN: 0038-0717; 1879-3428; 1879-3428
• DOI: 10.1016/j.soilbio.2009.10.021

In boreal forests ericaceous shrubs often dominate the forest floor vegetation. Nitrogen enrichment has been shown to decrease shrub abundance and in this study we explored whether it also affects the root associated fungal communities. Fine roots of Vaccinium myrtillus were collected in a Norway spruce dominated forest and of Vaccinium vitis-idaea in a Scots pine dominated forest. In both forests, nitrogen enrichment was experimentally induced by adding 12.5 and 50 kg N ha −1 yr −1 for 12 (spruce forest) and four (pine forest) years. Based on terminal restriction fragment length polymorphisms, subcloning and sequencing analyses, the root associated fungal communities were examined. We found 93 fungal species including Asco-, Basidio- and Zygo-mycota. In general, the Rhizoscyphus ericae aggregate was the most dominant and this was followed by Herpotrichiellaceae and Sebacina. Ordination analysis revealed that nitrogen enrichment did not change species composition of the fungal communities in neither the spruce nor the pine forest, while fungal community structures were clearly discriminated between the dominant shrub species in each forest. Similarly, no fungal species showed a significant response to nitrogen enrichment. Therefore, nitrogen enrichment appears to have no effect on root associated fungi of understorey dwarf shrubs in boreal forests, while it is clear that spruce and pine forests harbor distinctive communities of these fungi.